Search results
Results from the WOW.Com Content Network
Micrograph showing hemosiderin-laden alveolar macrophages, as seen in a pulmonary hemorrhage. H&E stain. An alveolar macrophage, pulmonary macrophage, (or dust cell) is a type of macrophage, a professional phagocyte, found in the airways and at the level of the alveoli in the lungs, but separated from their walls. [1]
The cells are primarily monocytes and macrophages, and they accumulate in lymph nodes and the spleen. The Kupffer cells of the liver and tissue histiocytes are also part of the MPS. The mononuclear phagocyte system and the monocyte macrophage system refer to two different entities, often mistakenly understood as one.
The short-term exposure attracts macrophages and neutrophils to the lung with a 4-fold increase in cellularity. [ 4 ] [ 2 ] Short duration also biases polarization towards M1 phenotype. The number of immune cells however will be normalized in 6 months, demonstrating the shift in signaling direction.
They are also called pulmonary macrophages, and dust cells. Alveolar macrophages also play a crucial role in immune responses against viral pathogens in the lungs. [25] They secrete cytokines and chemokines, which recruit and activate other immune cells, initiate type I interferon signaling, and inhibit the nuclear export of viral genomes. [25]
A siderophage is a hemosiderin-containing macrophage. Heart failure cells are siderophages generated in the alveoli of the lungs of people with left heart failure or chronic pulmonary edema, when the high pulmonary blood pressure causes red blood cells to pass through the vascular wall. [1] Siderophages are not specific of heart failure.
Mucociliary clearance (MCC), mucociliary transport, or the mucociliary escalator describes the self-clearing mechanism of the airways in the respiratory system. [1] It is one of the two protective processes for the lungs in removing inhaled particles including pathogens before they can reach the delicate tissue of the lungs.
Lipid-laden alveolar macrophages, also known as pulmonary foam cells, [2] are cells found in bronchoalveolar lavage (BAL) specimens that consist of macrophages containing deposits of lipids (fats). [3] The lipid content of the macrophages can be demonstrated using a lipid targeting stain like Oil Red O or Nile red.
Pulmonary surfactant thus greatly reduces surface tension, increasing compliance allowing the lung to inflate much more easily, thereby reducing the work of breathing. It reduces the pressure difference needed to allow the lung to inflate. The lung's compliance, and ventilation decrease when lung tissue becomes diseased and fibrotic. [3]